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new section for Cyberlindnera
==Yeasts==
===''Cyberlindnera'' spp.===
The organoleptic properties of several species from the genus ''Cyberlindnera'' have been studied with promising results for non-alcoholic wort fermentation. These results can also be applied to alcoholic mixed fermentation. Bellut et al (2019) reported pleasant fruity characteristics from 4 out of 6 strains of various species from this genus (the other two strains produced unpleasant solvent-like aromas). They did not produce significant alcohol (18-25% attenuation) and could not ferment maltose or maltotriose. While they all could ferment glucose, four of the six strains fermented sucrose and only one strain fermented fructose. IBU up to 100 were tested against these strains' ability to grow, and that high of an IBU had no reported effects. All strains tested did not produce phenols (POF-). Four of the six strains could tolerate up to 5% ABV, and two of those tolerated up to 7.5% ABV (the higher ABV resulted in longer lag times by 24-48 hours). All of the six strains tolerated a pH of 4 and five of the six strains tolerated a pH of 3 (only at a pH of 3 did the strains see an extended lag time during growth, from 12-78 hours depending on the strain), although the presence of lactic acid instead of the hydrochloric acid used in this study could have a stronger inhibitory effect. Glycerol production was low (0.18 - 0.36 mg/L). Two of the strains produced very high levels of acetaldehyde (9.7 and 8.1 mg/L), and one strain produced very high ethyl acetate (65.7 mg/L compared to 4.9-22.6 mg/L). Isoamyl acetate was produced at a wide range between the different strains, from 1.67 mg/L to 0.15 mg/L <ref name="Bellut_2019">[https://www.mdpi.com/2311-5637/5/4/103/htm Screening and Application of Cyberlindnera Yeasts to Produce a Fruity, Non-Alcoholic Beer. Konstantin Bellut, Maximilian Michel, Martin Zarnkow, Mathias Hutzler, Fritz Jacob, Jonas J. Atzler, Andrea Hoehnel, Kieran M. Lynch, and Elke K. Arendt. 2019. DOI: https://doi.org/10.3390/fermentation5040103.]</ref>.
Overall, the species that were favorable with fruity-like characteristics were: ''C. jadinii'', ''C. mrakii'', and two strains of ''C. subsufficiens''. The strains that were characterized as unpleasant were ''C. misumaiensis'' (described as solvent-like due to high levels of ethyl acetate) and ''C. fabianii'' (described as cabbage-like due to an unidentified aroma compound) <ref name="Bellut_2019" />.
====''Cyberlindnera subsufficiens''====
Due to the positive aroma characteristics and fermentation abilities in wort of one of the two strains of ''C. subsufficiens'' tested by Bellut et al. (2019) as mentioned above, the researchers chose to test for optimal fermentation conditions for this strain. It was determined that the highest fruitiness was achieved at the lowest fermentation temperature tested (62°F/17°C) and the lowest pitching rate (1 x 10<sup>10</sup> cells/mL), while the least fruitiness was achieved at the warmest fermentation temperature (80.6°F/27°C) and the highest pitching rate (6 x 10<sup>10</sup> cells/mL), following a linear model. They brewed a non-alcoholic beer with this strain and compared the sensory to two other non-alcohic beers (NAB) and found that the NAB brewed with ''C. subsufficiens'' tasted less like unfermented wort and more fruity and tropical than the other two commercial NAB products <ref name="Bellut_2019" />.
===''Debaryomyces'' spp.===